handle stop

lib/providers/timer_provider.dart

@@ -18,5 +18,8 @@ class TimerProvider extends ChangeNotifier {
     }));
   }
 
-  void stopTimer() => _timer?.cancel();
+  void stopTimer() {
+    started = false;
+    _timer?.cancel();
+  }
 }

lib/providers/workout_provider.dart

@@ -8,6 +8,7 @@ class WorkoutProvider extends ChangeNotifier {
   final AudioPlayer _audioPlayer = AudioPlayer();
   final Source _finishedSoundSource = AssetSource('finish.mp3');
   final Source _beepSoundSource = AssetSource('beep.mp3');
+  bool isWorkoutStarted = false;
 
   WorkoutProvider(this.timerProvider);
 
@@ -57,10 +58,19 @@ class WorkoutProvider extends ChangeNotifier {
   }
 
   void startWorkout() {
+    isWorkoutStarted = true;
     _audioPlayer.play(_beepSoundSource);
     _audioPlayer.onPlayerComplete.listen((event) {
       _audioPlayer.play(_phaseSongSources[currentPhase]!);
       timerProvider.startTimer(currentPhaseDuration);
     });
   }
+
+  void stopWorkout() {
+    isWorkoutStarted = false;
+    _workoutPhaseIndex = 0;
+    _audioPlayer.stop();
+    timerProvider.stopTimer();
+    notifyListeners();
+  }
 }

lib/widgets/workout_timer_widget.dart

@@ -25,7 +25,9 @@ class WorkoutTimerWidget extends StatelessWidget {
         Text(workoutProvider.currentPhase),
         TimerWidget(duration: workoutProvider.currentPhaseDuration),
         ElevatedButton(
-            onPressed: () => workoutProvider.startWorkout(),
+            onPressed: !workoutProvider.isWorkoutStarted
+                ? () => workoutProvider.startWorkout()
+                : () => workoutProvider.stopWorkout(),
             child: Text(timerProvider.started ? 'Stop' : 'Start'))
       ],
     );